If this was a game of COBOL one-upsmanship, I do believe I would win!

'Cause I think I am the ONLY geek in the world who has ever created a fully operational, full-screen editor coded entirely in... COBOL!!!
Despite my many (obvious) objections, I had a programming manager that insisted I write a full-screen editor for our internal users in COBOL where we could allow or disallow certain features (the "real" issue with the DEC EVE and EDT editors we already had). Yes, I ended up doing it and, yes, it DID work (albeit slow as snot). No idea why he was so stuck on COBOL, probably THE worst language he could have picked for that task!
So many of the other programmers were laughing at my having to do the project that word got up to the VP of IT and, when he walked into one of the Team Leader's offices and saw a code printout of it being used as wallpaper (it WAS very pretty), he investigated and we went with my original suggestion (using EVE with available modifications).
I'm still a little glad that he saw it after I had it finished and working though!
That said, I also programmed the fuzzy logic used to sync up cellular call records created by a single call as a user was handed off from tower to tower in COBOL. There were two main issues: One, we're talking about MILLIONS of call records (with over 2 BILLION in the Los Angeles area alone - the largest cellular market in the U.S.) and, two, the time stamps on all towers were always a little bit different.